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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /arch/xtensa/include/asm/processor.h
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/xtensa/include/asm/processor.h')
-rw-r--r--arch/xtensa/include/asm/processor.h257
1 files changed, 257 insertions, 0 deletions
diff --git a/arch/xtensa/include/asm/processor.h b/arch/xtensa/include/asm/processor.h
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+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2001 - 2008 Tensilica Inc.
+ * Copyright (C) 2015 Cadence Design Systems Inc.
+ */
+
+#ifndef _XTENSA_PROCESSOR_H
+#define _XTENSA_PROCESSOR_H
+
+#include <asm/core.h>
+
+#include <linux/compiler.h>
+#include <linux/stringify.h>
+#include <asm/ptrace.h>
+#include <asm/types.h>
+#include <asm/regs.h>
+
+/* Assertions. */
+
+#if (XCHAL_HAVE_WINDOWED != 1)
+# error Linux requires the Xtensa Windowed Registers Option.
+#endif
+
+/* Xtensa ABI requires stack alignment to be at least 16 */
+
+#define STACK_ALIGN (XCHAL_DATA_WIDTH > 16 ? XCHAL_DATA_WIDTH : 16)
+
+#define ARCH_SLAB_MINALIGN STACK_ALIGN
+
+/*
+ * User space process size: 1 GB.
+ * Windowed call ABI requires caller and callee to be located within the same
+ * 1 GB region. The C compiler places trampoline code on the stack for sources
+ * that take the address of a nested C function (a feature used by glibc), so
+ * the 1 GB requirement applies to the stack as well.
+ */
+
+#ifdef CONFIG_MMU
+#define TASK_SIZE __XTENSA_UL_CONST(0x40000000)
+#else
+#define TASK_SIZE __XTENSA_UL_CONST(0xffffffff)
+#endif
+
+#define STACK_TOP TASK_SIZE
+#define STACK_TOP_MAX STACK_TOP
+
+/*
+ * General exception cause assigned to fake NMI. Fake NMI needs to be handled
+ * differently from other interrupts, but it uses common kernel entry/exit
+ * code.
+ */
+
+#define EXCCAUSE_MAPPED_NMI 62
+
+/*
+ * General exception cause assigned to debug exceptions. Debug exceptions go
+ * to their own vector, rather than the general exception vectors (user,
+ * kernel, double); and their specific causes are reported via DEBUGCAUSE
+ * rather than EXCCAUSE. However it is sometimes convenient to redirect debug
+ * exceptions to the general exception mechanism. To do this, an otherwise
+ * unused EXCCAUSE value was assigned to debug exceptions for this purpose.
+ */
+
+#define EXCCAUSE_MAPPED_DEBUG 63
+
+/*
+ * We use DEPC also as a flag to distinguish between double and regular
+ * exceptions. For performance reasons, DEPC might contain the value of
+ * EXCCAUSE for regular exceptions, so we use this definition to mark a
+ * valid double exception address.
+ * (Note: We use it in bgeui, so it should be 64, 128, or 256)
+ */
+
+#define VALID_DOUBLE_EXCEPTION_ADDRESS 64
+
+#define XTENSA_INT_LEVEL(intno) _XTENSA_INT_LEVEL(intno)
+#define _XTENSA_INT_LEVEL(intno) XCHAL_INT##intno##_LEVEL
+
+#define XTENSA_INTLEVEL_MASK(level) _XTENSA_INTLEVEL_MASK(level)
+#define _XTENSA_INTLEVEL_MASK(level) (XCHAL_INTLEVEL##level##_MASK)
+
+#define XTENSA_INTLEVEL_ANDBELOW_MASK(l) _XTENSA_INTLEVEL_ANDBELOW_MASK(l)
+#define _XTENSA_INTLEVEL_ANDBELOW_MASK(l) (XCHAL_INTLEVEL##l##_ANDBELOW_MASK)
+
+#define PROFILING_INTLEVEL XTENSA_INT_LEVEL(XCHAL_PROFILING_INTERRUPT)
+
+/* LOCKLEVEL defines the interrupt level that masks all
+ * general-purpose interrupts.
+ */
+#if defined(CONFIG_XTENSA_FAKE_NMI) && defined(XCHAL_PROFILING_INTERRUPT)
+#define LOCKLEVEL (PROFILING_INTLEVEL - 1)
+#else
+#define LOCKLEVEL XCHAL_EXCM_LEVEL
+#endif
+
+#define TOPLEVEL XCHAL_EXCM_LEVEL
+#define XTENSA_FAKE_NMI (LOCKLEVEL < TOPLEVEL)
+
+/* WSBITS and WBBITS are the width of the WINDOWSTART and WINDOWBASE
+ * registers
+ */
+#define WSBITS (XCHAL_NUM_AREGS / 4) /* width of WINDOWSTART in bits */
+#define WBBITS (XCHAL_NUM_AREGS_LOG2 - 2) /* width of WINDOWBASE in bits */
+
+#ifndef __ASSEMBLY__
+
+/* Build a valid return address for the specified call winsize.
+ * winsize must be 1 (call4), 2 (call8), or 3 (call12)
+ */
+#define MAKE_RA_FOR_CALL(ra,ws) (((ra) & 0x3fffffff) | (ws) << 30)
+
+/* Convert return address to a valid pc
+ * Note: We assume that the stack pointer is in the same 1GB ranges as the ra
+ */
+#define MAKE_PC_FROM_RA(ra,sp) (((ra) & 0x3fffffff) | ((sp) & 0xc0000000))
+
+/* Spill slot location for the register reg in the spill area under the stack
+ * pointer sp. reg must be in the range [0..4).
+ */
+#define SPILL_SLOT(sp, reg) (*(((unsigned long *)(sp)) - 4 + (reg)))
+
+/* Spill slot location for the register reg in the spill area under the stack
+ * pointer sp for the call8. reg must be in the range [4..8).
+ */
+#define SPILL_SLOT_CALL8(sp, reg) (*(((unsigned long *)(sp)) - 12 + (reg)))
+
+/* Spill slot location for the register reg in the spill area under the stack
+ * pointer sp for the call12. reg must be in the range [4..12).
+ */
+#define SPILL_SLOT_CALL12(sp, reg) (*(((unsigned long *)(sp)) - 16 + (reg)))
+
+typedef struct {
+ unsigned long seg;
+} mm_segment_t;
+
+struct thread_struct {
+
+ /* kernel's return address and stack pointer for context switching */
+ unsigned long ra; /* kernel's a0: return address and window call size */
+ unsigned long sp; /* kernel's a1: stack pointer */
+
+ mm_segment_t current_ds; /* see uaccess.h for example uses */
+
+ /* struct xtensa_cpuinfo info; */
+
+ unsigned long bad_vaddr; /* last user fault */
+ unsigned long bad_uaddr; /* last kernel fault accessing user space */
+ unsigned long error_code;
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+ struct perf_event *ptrace_bp[XCHAL_NUM_IBREAK];
+ struct perf_event *ptrace_wp[XCHAL_NUM_DBREAK];
+#endif
+ /* Make structure 16 bytes aligned. */
+ int align[0] __attribute__ ((aligned(16)));
+};
+
+/* This decides where the kernel will search for a free chunk of vm
+ * space during mmap's.
+ */
+#define TASK_UNMAPPED_BASE (TASK_SIZE / 2)
+
+#define INIT_THREAD \
+{ \
+ ra: 0, \
+ sp: sizeof(init_stack) + (long) &init_stack, \
+ current_ds: {0}, \
+ /*info: {0}, */ \
+ bad_vaddr: 0, \
+ bad_uaddr: 0, \
+ error_code: 0, \
+}
+
+
+/*
+ * Do necessary setup to start up a newly executed thread.
+ * Note: When windowed ABI is used for userspace we set-up ps
+ * as if we did a call4 to the new pc.
+ * set_thread_state in signal.c depends on it.
+ */
+#if IS_ENABLED(CONFIG_USER_ABI_CALL0)
+#define USER_PS_VALUE ((USER_RING << PS_RING_SHIFT) | \
+ (1 << PS_UM_BIT) | \
+ (1 << PS_EXCM_BIT))
+#else
+#define USER_PS_VALUE (PS_WOE_MASK | \
+ (1 << PS_CALLINC_SHIFT) | \
+ (USER_RING << PS_RING_SHIFT) | \
+ (1 << PS_UM_BIT) | \
+ (1 << PS_EXCM_BIT))
+#endif
+
+/* Clearing a0 terminates the backtrace. */
+#define start_thread(regs, new_pc, new_sp) \
+ do { \
+ unsigned long syscall = (regs)->syscall; \
+ memset((regs), 0, sizeof(*(regs))); \
+ (regs)->pc = (new_pc); \
+ (regs)->ps = USER_PS_VALUE; \
+ (regs)->areg[1] = (new_sp); \
+ (regs)->areg[0] = 0; \
+ (regs)->wmask = 1; \
+ (regs)->depc = 0; \
+ (regs)->windowbase = 0; \
+ (regs)->windowstart = 1; \
+ (regs)->syscall = syscall; \
+ } while (0)
+
+/* Forward declaration */
+struct task_struct;
+struct mm_struct;
+
+/* Free all resources held by a thread. */
+#define release_thread(thread) do { } while(0)
+
+extern unsigned long get_wchan(struct task_struct *p);
+
+#define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc)
+#define KSTK_ESP(tsk) (task_pt_regs(tsk)->areg[1])
+
+#define cpu_relax() barrier()
+
+/* Special register access. */
+
+#define xtensa_set_sr(x, sr) \
+ ({ \
+ __asm__ __volatile__ ("wsr %0, "__stringify(sr) :: \
+ "a"((unsigned int)(x))); \
+ })
+
+#define xtensa_get_sr(sr) \
+ ({ \
+ unsigned int v; \
+ __asm__ __volatile__ ("rsr %0, "__stringify(sr) : "=a"(v)); \
+ v; \
+ })
+
+#if XCHAL_HAVE_EXTERN_REGS
+
+static inline void set_er(unsigned long value, unsigned long addr)
+{
+ asm volatile ("wer %0, %1" : : "a" (value), "a" (addr) : "memory");
+}
+
+static inline unsigned long get_er(unsigned long addr)
+{
+ register unsigned long value;
+ asm volatile ("rer %0, %1" : "=a" (value) : "a" (addr) : "memory");
+ return value;
+}
+
+#endif /* XCHAL_HAVE_EXTERN_REGS */
+
+#endif /* __ASSEMBLY__ */
+#endif /* _XTENSA_PROCESSOR_H */